1. Field of the Invention
The present invention relates to an exposure apparatus and exposure method for exposing a substrate, and to a device manufacturing method.
2. Description of Related Art
As an exposure apparatus for use in the photolithography process, there is proposed an immersion exposure apparatus as disclosed in PCT International Patent Publication No. WO 99/49504, in which a liquid is filled in an optical path space of the exposure light and a substrate is exposed via the liquid.
If impurities are mixed in the liquid that is filled in the optical path space of the exposure light, there is a possibility that defective exposure occurs such as faults in the pattern formed on the substrate.
A purpose of some aspects of the present invention is to provide an exposure apparatus and exposure method that can suppress the occurrence of defective exposure. Another purpose is to provide a device manufacturing method using the exposure apparatus and the exposure method.